In many cleaning applications, it is desirable to remove contaminants (e.g., stains) from substrates, like metal, ceramic, polymeric, composite, glass and textile comprising substrates. Particularly, it is highly desirable to remove contaminants from clothing whereby such contaminants include dirt, salts, food stains, oils, greases and the like.
Typically, dry cleaning systems use organic solvents, like chlorofluorocarbons, perchloroethylene, and branched hydrocarbons to remove contaminants from substrates. In response to environmental concerns, however, other dry cleaning systems have been developed that use inorganic solvents, such as densified carbon dioxide, to remove contaminants from substrates. The systems that use organic or inorganic solvents to remove contaminants from substrates generally employ a surfactant and a polar solvent so that a reverse-micelle may be formed to trap the contaminant targeted for removal.
Regardless of the type of solvents and surfactants employed, it is often very difficult to remove contaminants from substrates. This is true because contaminants often are chemically attracted to (e.g., dipole-dipole interactions, van der Waals forces) or become entangled with the substrate they are associated with. In fact, many known dry cleaning processes typically do not display superior cleaning results.
It is of increasing interest to develop compositions and methods that can be used to remove substantially all contaminants from substrates. This invention, therefore, is directed to a superior dry cleaning composition and method for dry cleaning that unexpectedly result in a substrate substantially free of contaminants (e.g., an SRI of at least about 64.0 as defined below) after cleaning and without the need to employ a displacing gas. Also, it is not required in this invention to use additives in the stain removal composition of the dry cleaning composition that are soluble in a continuous phase. Particularly, it is not required in this invention to employ a stain removal surfactant or an anti-redeposition agent, or both that is/are soluble in the continuous phase (as defined below).